title: [Pharmacokinetics of oral prazepam].
abstract: The biotransformation pathways following oral administration of prazepam are characterized. The time course of the active metabolite descyclopropylmethylprazepam (= norprazepam), representing 80-90% of all prazepam metabolites in plasma, can be described by an open one compartment model with a mean elimination half life of 70 h and a plasma clearance of 1.0-1.4 l/h. 3-5 h after single doses of 20 mg prazepam, the corresponding peak levels of norprazepam are 120-160 ng/ml. There is only a slight uptake of norprazepam into red blood cells and a relative low secretion into breast milk. Following repeated doses of daily 20 mg prazepam steady state levels of norprazepam are 600-800 ng/ml. The slow build-up of the active metabolite and the long elimination half life ensure continuous plasma levels with small fluctuations.
mesh_terms: D000284:Administration, Oral; D001711:Biotransformation; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008657:Metabolic Clearance Rate; D003708:Nordazepam / Q000378:metabolism; D010076:Oxazepam / Q000378:metabolism; D011222:Prazepam / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D003708:Nordazepam; D010076:Oxazepam; D011222:Prazepam
vernacular_title: Zur Pharmokokinetik nach oraler Gabe von Prazepam.